Preparation And Performance Of Superhydrophobic/superoleophobic Wear-resistant Cotton Fabrics Based On Polydopamine

In recent years,the superhydrophobic textiles,which are one of the functional textiles,have the unique properties of self-cleaning,anti-fouling,anti-fog,anti-ice and snow adhesion performance and potential applications,and attracte much attention by the researchers and customers.In the 1950 s,DuPont Co.Ltd.firstly used the fluorine-containing finishing materials to endow the surface of textiles with superhydrophobicity.However,the researchers find the fluorine-containing materials are not able to degradate in nature environment with the deeper investigation and rapid development of scitific technology.Meanwhile,the fluorine-containing materials are able to bioaccumulate so that it brings the potential harmness to humanity,indicating that the fluorine-free superhydrophobic textiles have the great prospect in the future.As the previous studies reported,superhydrophobic or superoleophobic textiles have the drawback that the wear-resistance is poor in the used processing,demonstrating that the textiles with sustainable and durable superhydrophibicity or superoleophobicity is one of the major challenges.Inspired by this analysis,the major content of this thesis included three parts as follows:First,inspired by the mussels with strong adhesion,the dopamine was utilized to endow the surface of cotton fabric with polydopamine coating,subsequently the roughness of the coating surface was obtained from the modified by nickel sulfate solution.Then,the ethanol solution of ODA was employed to reduce the surface free energy of cotton fabric so that the fluorinate-free superhydrophobic wear-resistant cotton fabric was successfully fabricated.As a result from the experiment,the modified cotton fabric still reserved superhydrophobic property after 500 cycle's abrasion and exhibited good hydrophobicity after 1000 cycle's abrasion.Therefore,the surface of cotton fabric was endowed with durable superhydrohpobic property,indicating that the drawback that the existing superhydrohpobic cotton fabric has poor wear-resistance was overcome.Secondly,in order to reduce the procedure of fabricating superhydrohpobic cotton fabric,the dipping coating method was employed to obtain the fluorinate-free superhydrohpobic cotton fabric with wear-resisitance.The hydrophobic resin was employed to form a hydrophobic film,subsequently the octadecylamine was firmly adhered onto the cotton fabric surface,owning to the strong adhesion from hydrophobic resin and indicating that the the roughness of cotton fabric surface was improbed and the surface free energy was reduced.As a result,the limitation that traditional methods frequently utilize additional nanoparticles to construct hierarchical rough surfaces was broken.The results of experiments showed that the contact angle of water on the cotton fabric surface was reached 154.4±0.6°,and the water contact angle was 151.5±0.4°after 30 cycle's abrasion.In addition,the modified cotton fabric was still great resistant to water at different temperature.Finally,in view of the fact that the superhydrophobic surface is easy to be polluted by oil and lose its superhydrophobic function,therefore the superoleophobic and hydrophobic wear-resistanct cotton fabric was fabricated.Folic acid is able to self-aggregate under the condition of heating,and then induce the dopamine to from the nano-and microparticles of polydopamine,depositing on the surface of cotton fabric and endowing the surface with certain roughness.In order to improve the roughness,the Ammonium hexafluorosilicate,3,5-Bis(trifluoromethyl)aniline and surfactants of fs-81 and fs-63 was utilized to modify the particles of polydopamine.3,5-Bis(trifluoromethyl)aniline reacted with the phenolic hydroxyl groups of polydopamine nanoparticles via Schiff base reaction.Ammonium hexafluorosilicate was adsorbed on the surface of polydopamine microspheres via electrostatic interactions.Then,the self-assembly behavior of fs-81 and fs-63 with ammonium hexafluorosilicate occurred on polydopamine nanoparticles via electrostatic interactions,and formed micro-and nanoparticles to improve the roughness of cotton fabric and reduce the surface free energy.The results showed that the contact angles of the cotton fabric surface with edible oil,ethylene glycol and glycerol were greater than 150° in the air,respectively.Additionally,the contact angles between the cotton fabric surface and edible oil droplets were still greater than 150° after 25 abrasion cycles.